KR20110067591A - Control method for refrigerator - Google Patents

Abstract

PURPOSE: A method of controlling a refrigerator is provided to use a refrigerant cycle, in which two compressors are serially connected and two evaporators are connected in parallel, and to reduce the fluctuation on the inner temperature of the refrigerator by driving the compressors in a stabilized state. CONSTITUTION: A method of controlling a refrigerator is as follows. The refrigerator comprises first and second compressors, a condenser, a first expansion valve, a second expansion valve, a first evaporator, a second evaporator, and a control valve. The second evaporator is connected to the entrance of the first compressor and the first evaporator is connected to the entrance of the second compressor. The inner temperature(TR) of a refrigerating compartment and the inner temperature of a freezing compartment are monitored every cycle. Both the first compressor and the second compressor are driven when at least, TF>=Ta+dT (S18) Both valves of the refrigerating and freezing compartments are opened until TR<=Ta-dT(S15), where Ta represents the target temperature of the refrigerating compartment and dT is deviation.

Description

Control method for refrigerator

The present invention relates to a control method of a refrigerator.

Generally, a refrigerator is a home appliance for storing food at a low temperature.

In detail, the refrigerator utilizes a refrigeration cycle consisting of a compressor, a condenser, an expansion device, and an evaporator, and allows the cold air generated by the evaporator to be supplied to the space for food storage.

In addition, the conventional refrigerator is most of a type provided with a single compressor and a single evaporator, and a type provided with a single compressor and two evaporators.

For example, in the case of a refrigerator cycle in which two evaporators are connected in parallel to one compressor, either one of the two evaporators is the freezer evaporator and the other is the refrigerator compartment evaporator. In the case of such a refrigerator cycle, since the refrigerating compartment has a faster load increase rate than the freezer compartment, operation is performed in the order of the refrigerating compartment cooling, the freezing compartment cooling, and the stop of the compressor. When the refrigerator compartment temperature reaches the set temperature, the operation of the three-way valve is controlled to allow the refrigerant to flow to the freezer compartment evaporator.

In the case of the refrigerator cycle as described above, the refrigerant is selectively sent to either the refrigerating chamber evaporator or the freezing chamber evaporator, and the temperature in the other chamber continues to rise until either of the inside chamber temperatures is satisfied. As a result, there is a disadvantage that the fluctuation of the internal temperature is relatively large.

In addition, since the alternating operation for alternately driving the refrigerant cycle by alternately sending the refrigerant to the refrigerator compartment evaporator and the freezer compartment evaporator, and the intermittent operation of repeatedly operating and stopping the compressor, the temperature of the evaporator is lower than that of the continuous operation. As a result, there is a disadvantage that the efficiency of the refrigerant cycle is low.

The present invention is proposed to improve the above disadvantages, to provide a control method of a refrigerator that can reduce the fluctuation of the internal temperature of the refrigerator during operation of the refrigerant cycle, and at the same time increase the efficiency of the refrigerant cycle. The purpose.

In the control method of the refrigerator according to the embodiment of the present invention for achieving the above object, in the operation control method of the refrigerator, the refrigerator, the first compressor and the second compressor connected in series, the outlet side of the compressor And a refrigerating chamber expansion valve and a freezing chamber expansion valve connected in parallel at the outlet side of the condenser, a refrigerating chamber evaporator and a freezing chamber evaporator respectively connected to the expansion valves, and a refrigerating chamber expansion valve and a freezing chamber expansion valve. And a control valve for controlling the flow direction of the refrigerant, wherein the freezer compartment evaporator has a refrigeration cycle connected to the inlet side of the first compressor, and the refrigerating compartment evaporator has a refrigeration cycle connected to the inlet side of the second compressor. Detecting the temperature TR and the freezer compartment internal temperature TF at regular intervals; Driving both the first compressor and the second compressor when at least TF ≧ Ta + dT (Ta: refrigerating chamber target temperature, dT: deviation value); And opening both the refrigerating compartment valve and the freezing compartment valve until TR ≦ Ta-dT is satisfied.

According to the control method of the refrigerator according to the embodiment of the present invention having the above-described configuration, two compressors are connected in series, and two evaporators use a refrigerant cycle connected in parallel. By performing the continuous operation, there is an effect that the fluctuation range of the refrigerator internal temperature decreases.

In addition, since the internal temperature of the refrigerator is cooled to a temperature lower than the set temperature in the continuous operation state, the refrigerator is switched to the freezer cooling mode, and thus, even if the fluctuation range of the internal temperature is set small, the continuous operation state of the compressor is maintained, thereby increasing cycle efficiency. There is this.

Furthermore, since the on / off frequency of the compressor is reduced, the effect of reducing the power consumption can also be obtained.

Hereinafter, a control method of a refrigerator according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a configuration diagram of a refrigerant cycle of a refrigerator according to an embodiment of the present invention.

1, the refrigerant cycle 10 of the refrigerator according to the embodiment of the present invention, the compressor (11); A condenser (13) connected to the outlet side of the compressor (11); An expansion valve (15) connected to the outlet side of the condenser (13); An evaporator 16 connected to the outlet side of the expansion valve 15 and a control valve 14 provided between the condenser 13 and the expansion valve 15.

In detail, the expansion valve 15 includes a freezing compartment side expansion valve 151 and a refrigerating chamber side expansion valve 152, and the evaporator 16 includes a freezer compartment side evaporator 161 connected to the freezer compartment expansion valve 151; The refrigerator compartment side evaporator 162 is connected to the refrigerator compartment side expansion valve 152. In addition, the freezer compartment side expansion valve 151 and the refrigerating compartment side expansion valve 152 are branched at the outlet side of the condenser 13, and the control valve 14 is mounted at the branched point. In addition, the control valve 14 allows the refrigerant to be supplied to any one or both of the freezing compartment side expansion side 151 and the refrigerating compartment side expansion side 152.

In addition, the compressor 11 is connected to the first compressor 111 and the first compressor 111 that are always operated when the refrigerant cycle is driven, when the refrigerant is supplied only toward the refrigerating chamber side evaporator 162. The second compressor 112 is stopped from operation.

In detail, a three-way valve may be applied as the control valve 14 to allow the refrigerant to be supplied to any one or both of the freezing compartment side expansion side 151 and the refrigerating compartment side expansion side 152. As another embodiment of the control valve 14, an opening and closing valve is provided at an inlet of the freezing compartment side expansion valve 151 and an inlet of the refrigerating compartment side expansion valve 152, respectively, according to an operation mode. Can be controlled.

In the following description, the opening or opening / closing state of the valve to be supplied to the freezing compartment side expansion valve 151 is defined as the refrigerator compartment valve being turned on, and the opening or opening / closing state of the valve so that the refrigerant is supplied to the refrigerator compartment expansion valve 152 is It will be described by defining that the freezer valve is turned on. And, since the claims of the present invention will also be described in accordance with the above definition, it should be understood that the control valve 14 should not be construed as limited to a separate open / close valve.

2 is a flowchart illustrating a control method of a refrigerator according to an exemplary embodiment of the present invention, which is a flowchart illustrating driving control of a compressor and a valve according to temperature changes in a refrigerator compartment and a freezer compartment in a stable state.

In the following description of the control method, it will be described on the premise that a component including a controller of a refrigerator, a temperature sensor for detecting a temperature in a refrigerator, a driver for driving a compressor, a control valve, and the like is provided. .

Referring to FIG. 2, the internal temperature sensor periodically detects a refrigerator compartment temperature TR and a freezer compartment temperature TF. Then, the detected temperature is transmitted to the controller, and the controller first determines whether the refrigerator compartment temperature TR is unsatisfactory (11). Here, the unsatisfactory state means a case where the refrigerating chamber temperature TR is equal to or higher than the upper limit temperature at which cold air supply is required. In other words,

TR≥Ta + dT (Ta: refrigerator set temperature, dT: set deviation value)

Say if you are satisfied. Here, the setting deviation value dT may be set to a value smaller than the setting deviation value applied to the conventional control method. In addition, according to the refrigerant cycle and the control method according to the embodiment of the present invention, the set deviation value can be reduced as compared with the conventional, even if the set deviation value is smaller than the conventional case, the number of on / off of the compressor is reduced, Power consumption is reduced and cycle efficiency is increased.

On the other hand, if it is determined that the refrigerator internal temperature TR is equal to or higher than the upper limit temperature, a simultaneous operation mode in which the first compressor 111 and the second compressor 112 are simultaneously driven is performed (12). Then, both the refrigerator compartment valve and the freezer compartment valve are opened (13).

In addition, it is determined whether or not the temperature inside the refrigerating chamber refrigerator sensed by the temperature sensor in a state in which both the refrigerating chamber valve and the freezing chamber valve are open (14). The satisfactory state herein means a case where the refrigerating chamber temperature TR is equal to or lower than the lower limit temperature at which cold air supply is stopped. That is, the case where TR ≦ Ta-dT is satisfied. When the refrigerating compartment temperature TR is determined to be lower than or equal to the lower limit temperature, the refrigerating compartment valve is closed and the valve is controlled to maintain only the freezer compartment valve (15). Here, the speed of increasing the load of the refrigerating compartment can be lowered by lowering the temperature by the temperature inside the refrigerating compartment high-stored temperature corresponding to the deviation value dT. That is, the load increase of the refrigerating compartment generated in the process of cooling the freezer compartment may be delayed.

In addition, it is determined whether or not the temperature inside the freezer compartment detected by the temperature sensor in a state where only the freezer compartment valve is opened is satisfied (16). Herein, the freezing chamber high temperature temperature means a case where the freezing chamber temperature TF is equal to or lower than the lower limit temperature at which cold air supply is stopped. That is, the case where TF ≦ Tb-dT is satisfied. When the freezer compartment temperature TF is determined to be lower than or equal to the lower limit temperature, the internal temperature TR of the refrigerating compartment is sensed. That is, the step S11 or less process of determining whether the internal temperature TR of the refrigerating chamber is unsatisfactory is repeated.

On the other hand, if it is determined that the internal temperature TR of the refrigerating compartment is not unsatisfactory, that is, if the detected refrigerating compartment internal temperature is within the range of TR <Ta + dT, it is determined whether the freezer compartment internal temperature is unsatisfactory (17). ).

In detail, when the temperature inside the freezer compartment is in an unsatisfactory state, that is, when TF ≧ Tb + dT, a simultaneous operation mode in which the first compressor 111 and the second compressor 112 are simultaneously driven is performed. At the same time, only the freezer compartment valve is opened to allow cold air to be supplied to the freezer compartment. On the other hand, if it is determined that the freezer compartment internal temperature TF is not unsatisfactory, the process of continuously detecting the internal temperature of the refrigerator compartment and the freezer compartment is repeatedly performed. Here, while the power of the refrigerator is kept on, the compressor continuously detects the internal temperature of the refrigerator while maintaining the continuous operating state (19). However, when the internal temperatures of the refrigerating compartment and the freezing compartment are lower than the lower limit temperature and overcooled, the operation of the compressor can be controlled to stop.

In the case of opening or closing the refrigerating compartment door or the freezing compartment door, or bringing food into the refrigerator, a state without a sudden increase in the load inside the refrigerator may be referred to as a stabilized state. The continuous operation state in which the compressor 112 does not stop driving is maintained, so that power consumption generated when the compressor starts to operate can be reduced. In addition, when the continuous operation state is maintained, since the cooling capacity of the compressor can be maintained at a low state, there is an advantage in that power consumption is reduced while the compression work is reduced.

Hereinafter, the operation control method for the refrigerator compartment load corresponding to the load in the refrigerator compartment high load will be described.

3 is a flowchart illustrating a method for controlling operation of a refrigerator compartment load corresponding to a refrigerator according to an embodiment of the present invention.

Referring to FIG. 3, the refrigerant cycle is basically operated in the operation mode in the stabilized state as described with reference to FIG. 2. In addition, the controller detects whether a cause of the sudden increase in the load in the refrigerating chamber is detected (22). Here, the causes of the increase in the refrigerating compartment load, first, when a high temperature food is put into the refrigerating compartment, second, when opening and closing the refrigerating compartment door, third, between the temperature sensor mounted at various points inside the refrigerating compartment for a specific reason The case where a temperature difference is large is mentioned. That is, it may be determined whether the load of the refrigerating compartment is rapidly increased from the temperature information and the door opening information transmitted from the internal temperature sensor or the door opening detecting sensor.

In detail, when it is determined that the refrigerating compartment load has increased, only the refrigerating compartment valve is opened and the freezing compartment valve is closed (23). Then, the compression work (speed) of the first compressor 111 is increased (24). Here, since only the refrigerating compartment valve is operated in an open state, a pump-down process in which the refrigerant of the freezing compartment evaporator 161 is recovered to the compressor is performed. The first compressor 111 and the second compressor 112 are connected in series, and the refrigerator compartment evaporator 162 and the freezer compartment evaporator 161 are connected in parallel to the freezer compartment evaporator 161. This is because the refrigerant pipe is closed.

On the other hand, when the pump down process for recovering the refrigerant in the freezer compartment evaporator 161 is terminated (25), the driving of the second compressor 112 is stopped (26). When the internal temperature TR of the refrigerating compartment drops to the lower limit temperature TR ≦ Ta-dT (27), depending on whether the refrigerator is turned off, the compressor is stopped or switched to a stable operation mode. (28).

4 is a flowchart illustrating a method for controlling operation corresponding to a freezer compartment load of a refrigerator according to an exemplary embodiment of the present invention.

Referring to FIG. 4, the refrigerant cycle is basically operated 31 in the operating mode in the stabilized state as described with reference to FIG. 2. In operation 32, the controller detects whether a cause of the freezer load surge has occurred. In addition, it is assumed that the cause of the freezer load surge is the same as the cause of the refrigerator compartment load surge.

On the other hand, when the cause of the freezer load surge is detected, the refrigerator compartment valve is closed and only the freezer compartment valve is opened (33). Then, the compression work (speed) of the first compressor 111 and the second compressor 112 is increased (34) to cool the freezer compartment. Then, it is determined whether or not the freezer compartment internal temperature has reached the lower limit temperature (TF ≦ Tb-dT) (35). When it is determined that the freezer compartment temperature reaches the lower limit temperature, the compressor is stopped or switched to the operation mode in a stabilized state depending on whether the refrigerator is powered off (36).

According to the control method as described above, the fluctuation range of the existing refrigerating chamber or freezing chamber temperature can be reduced, and at the same time, the number of on / off of the compressor can be reduced, thereby reducing power consumption. Furthermore, the effect of increasing the cycle efficiency of the refrigerator can be obtained.

5 is a graph showing a comparison between the temperature fluctuations in the refrigerator according to the control method of the refrigerator according to an embodiment of the present invention and the temperature fluctuations in the conventional refrigerator.

Referring to FIG. 5, in the related art, it can be seen that the temperature fluctuation range of the refrigerating compartment or the freezing compartment is relatively larger than that of the present invention.

Taking the refrigerating compartment as an example, when the compressor operation is stopped or when only the freezing compartment is cooled, the temperature of the refrigerating compartment in which cold air is not supplied increases. In the state where the compressor starts or cools the refrigerating compartment, the temperature of the refrigerating compartment decreases. However, as in the conventional case, in the case of the refrigeration cycle in which the continuous operation mode is not applied or in the case of one compressor, the width interval between the upper limit temperature and the lower limit temperature becomes large.

However, as in the present invention, by maintaining the continuous operation mode and the simultaneous cooling mode in the stabilization state where the load fluctuation is not large, and by applying the alternate cooling mode only in the load-corresponding operation mode, the high temperature increase / decrease in the high temperature does not increase greatly from the set temperature. Will not. Therefore, even if the deviation value is set small from the refrigerator internal setting temperature, the on / off frequency of the compressor is significantly reduced as compared with the related art.

1 is a refrigerant cycle configuration of a refrigerator according to an embodiment of the present invention.

2 is a flowchart showing a control method of a refrigerator according to an embodiment of the present invention, which shows a drive control of a compressor and a valve according to temperature changes in a refrigerator compartment and a freezer compartment in a stable state.

3 is a flowchart illustrating a method for controlling operation of a refrigerator compartment load corresponding to a refrigerator according to an embodiment of the present invention.

4 is a flowchart showing a method for controlling operation corresponding to a freezer compartment load of a refrigerator according to an exemplary embodiment of the present invention.

5 is a graph showing a comparison between the temperature fluctuations in the refrigerator and the temperature fluctuations in the conventional refrigerator according to the control method of the refrigerator according to an embodiment of the present invention.

Claims (13)

In the operation control method of the refrigerator, The refrigerator includes a first compressor and a second compressor connected in series, a condenser provided at an outlet side of the compressor, a refrigerating chamber expansion side and a freezer compartment expansion side connected in parallel at an outlet side of the condenser, and the expansion sides, respectively. A refrigerator compartment evaporator and a freezer compartment evaporator, and a control valve provided at a point divided into the refrigerator compartment side expansion valve and the freezer compartment side expansion valve to control a flow direction of the refrigerant, wherein the freezer compartment evaporator is connected to the inlet side of the first compressor, The refrigerating compartment evaporator has a refrigeration cycle connected to the inlet side of the second compressor, Detecting the refrigerator compartment inside temperature TR and the refrigerator compartment inside temperature TF at regular intervals; Driving both the first compressor and the second compressor when at least TF ≧ Ta + dT (Ta: refrigerating chamber target temperature, dT: deviation value); And  And refrigerating chamber valve and freezing chamber valve are opened until TR ≦ Ta-dT is satisfied. The method of claim 1, When TR≤Ta-dT, the refrigerating chamber valve is closed by the operation of the control valve, And only the freezer compartment valve is opened until TF ≦ Tb-dT (Tb: freezer compartment target temperature, dT: deviation) is satisfied. The method of claim 1, The state in which the first compressor and the second compressor are stopped, A method of controlling the operation of a refrigerator, which is maintained until at least one of TR≥Ta-dT or TF≥Tb-dT is satisfied. The method of claim 1, The dT is the operation control method of the refrigerator, characterized in that 0.2. The method of claim 1, When it is detected that the refrigerating chamber load is rapidly increased while the first compressor and the second compressor are in operation, And a freezer compartment expansion valve is closed by an operation of the control valve, and the operation control method of the refrigerator is switched to a refrigerating compartment load corresponding operation mode in which only the refrigerator compartment side expansion valve is opened. The method of claim 5, Whether the refrigerating chamber load has surged, When it is detected that a difference in detection value between a plurality of temperature sensors mounted at different positions in the refrigerator is outside the setting range; When the refrigerator door opening is detected by the refrigerator door opening detecting means; And And at least one or more of cases where it is determined that the temperature lowering speed is lower than the set value from the temperature value detected by the temperature sensor in the refrigerator. The method of claim 5, When entering the refrigerator load load operation mode, Operation control method of the refrigerator characterized in that the control to increase the compression work of the first compressor. The method according to claim 5 or 7, With the freezer valve closed, When the pump down process (pump down) of the refrigerant in the freezer compartment evaporator is completed, And controlling the driving of the second compressor to be stopped. The method of claim 8, The refrigerating chamber load corresponding operation mode is performed until TR ≦ Ta-dT is satisfied. Thereafter, the operation control method of the refrigerator, characterized in that the operation mode before the sudden increase in load. The method of claim 1, When it is detected that the load of the freezer compartment is rapidly increased while the first compressor and the second compressor are in operation, The operation control method of the refrigerator, characterized in that the refrigerating chamber valve is closed, the operation mode of the refrigerator is switched to a freezer load corresponding operation mode in which only the freezing chamber valve is opened. 11. The method of claim 10, Whether the freezer load has surged, When the difference in sensed values between the plurality of temperature sensors mounted at different locations in the refrigerator is detected to be out of a setting range; When the freezer door opening is detected by the freezer door opening detecting means; And And at least one or more of cases where it is determined that the temperature lowering speed is lower than the set value from the temperature value detected by the temperature sensor in the refrigerator. 11. The method of claim 10, In the operation mode corresponding to the freezer compartment load, the operation control method of the refrigerator, characterized in that controlled to increase the compression days of the first compressor and the second compressor. The method according to claim 10 or 12, The freezer load corresponding operation mode is performed until TF≤Tb-dT is satisfied. After that, the operation control method of the refrigerator, characterized in that switching to the operation mode before the load surge.

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